Electric drive for calculating machines



Sept. 28,1926. e1,601,102

F. W. BERNAU EL'EcTRIc DRIVE Fon CALCULATING MACHINES Filed Jan. 19,1924 a'sheets-shent 1 Sept. 28,1926. 1,601,102

. F. W. BERNAU ELECTRIC DRIVE FOR CALCULATING MACHINES Filed Jan. 19,1924 3 Shets-Sheot 2 Sept. 28 1926. I 1,601,102 F, lw. BERNAU ELECTRICDRIVE FOR CALCULATING MACHINES Filed Jan. 19, 1924 3 Sheets-Sheet 3Patented Sept. 28, 1926.

UNITED STATES PATENT ePRICE.

FREDERICK W. BERNAU, OF HILLSIDE, NEW JERSEY, ASSIGNOR TO ELLIS ADDING-TYPEWRITER COMPANY, F NEWARK,

JERSEY.

lNEW JERSEY, A CORPORATION OF NEW ELECTRIC DRIVE FOR CALCULATINGMACHINES. I'

Application led January 19, 1924. Serial 0.687,395.

This invention relates to those motor driven mechanisms, commonly knownas has become engaged, cause the calculatingy machine to go through itscycle of operations, and then to automatically throw out or release theclutch, unlessl the starting bar or key is held in its operativeposition; Electric drives for the purpose set forth are subject tosudden shock when the clutch is engaged, this shock being communicatedto the mechanism of the calculating machine.k I therefore provide means.in the nature of a yielding drive or coupling, interposed between theworm pinion and the motor shaft'to absorb the shock when the clutchv isthrown in and to thus start the mechanism of the sudden jar.

The yielding drive or coupling for the Worm pinion will, under usualconditions,

hold suiciently to transmit 'the driving 'action of the motor to themechanism of the calculating machine but if', for any reason, themechanism of the calculating machine has become locked orofersvm'ore'thanthe pling will permit slippage sothat, whilethe motorwill continue to operate, no damage will be done toeither the drivingmechanism lating machine'. l V

Electric drives for operatingcalculating machines must'be positive intheir clutching and de-clutching actions, have no overthrow, possessextreme durability,I `md be simple and invariably accurate, aswell asadalpted to clutch andV de-cl'utch quickly and wit out possibility offailure.Y

`calculating machine without usual resistance. ,the ryielding drive,orcou-y My electric drive embodies improvements and novel combinationsof elements by which the mechanism fulfills all of the foregoingrequirements.- The worm gear is provided with a plurality of engageabledevices, which may be holes, and constitutes the continuously drivenmember of the clutch. y The other member of the clutch is a normallystationary, rotarily mounted, plate' or disk which carries a .driving inpositloned to engage the nearest engagea le device, orhole, of the wormgear. The driving pin is ada ted to establish the engagement aforesaiwhen it is released but is normally restrainedby a yrestoring latchcooperating with an improved operating lever combined with the startingbar of the calculating machine. 'l

When the starting bar is depressed, the restoring klatch is freedand,vthe1jeupon, spring means snaps the driving pin into the nearesthole of the worm gear, thus coupling the driving plate to the worm gearso `that it rotates with the latter for onecomplete revolutionwhereuponity is automatically retracted by the re-engagement'- of `therestoringlatch' with' the operating 'lever' un-- less the startingbar'is held down; in the latter event the drivingy plate Vcontinues vtorotate with the 'worm gear as long yas ithe Starting'bar remainsdepressed.

The operating' means of :the calculatingV machinehas an operativeconnection to .the

drivin plate and said 4operating means ofthe ca culating machine willbe, actuated lonce, or as many times as desired, according to themanipulation vof the starting bar.

yAn improved device, in they nature ofa back stop pawl, providesmeanswhich prevents iash or swinging` movement of the driving plateandliolds it positively against, back kick when the driving plate iskar-k rested.

or the operatingmechanism of the 'calcu- '.The invention also embracesother ivmproved features and novel combinations of parts appearing morefully from the followmg descriptionfof the `practical embodiment I oftheinvention which is shown in the accompanying drawings.

I am aware that changes may be resorted to in carrying out the essentialprinciples of the invention which yis not intended to be limited to thedetails of construction hereinafter described except where specified inthe claims. I

In the accompanying drawings:

Figure 1 is a side elevation showing the electric drive combined with anEllis calculating machine, certain parts being in section and a part ofthe casing being omitted.

Fig. 2 is a vertical section on the line 2-2, Fig. 1 certain parts beingin full lines.

Fig. 3 is a detail vertical section through the lower part of thecasing, a lubricant reservoir,vworm and worm gear on the line 3-3, Fig.2.

Fig. 4 is a detail View of the restoring latch.

Fig. 5 is a plan view thereof.

Figs. 6 and 7 are front and side views of the driving collar. p

Fig. 8 is a plan view of the operating lever.

Fig. 9 is a front elevation thereof.

Fig. 10 is a front view of the spring which actuates the driving pin.

Fig. 11 is a plan view of the back stop pawl.

Fig. 12 is a front view thereof; and

Fig.. 13 is an end elevation thereof.

While the present invention is shown and described as combined with acalculating machine, it is to be understood that it is not restricted tothis use, nor to use with an Ellis calculating machine, as my electricdrive may be employed as a clutch in connection with other machines andfor other purposes where an effective positive clutch action with anautomatic throwout or declutching arrangement of simple form and greatdurability is required without the use of an oil bath for the parts torun in.

In F igure. 1 there is illustrated so much of the startmg bar andoperating mechaj nism of the Ellis machine disclosed in patents andapplications as will afford a clear understanding of the manner in whichthe present electric drive may be applied to said machine for thepurpose of operating it.

The base of the machine is shown at 1. The Ellis machine has a shaft 2to which is fastened adrive plate 3. The electric drive, hereinafterdescribed, is utilized to operate the calculating machine by links 4whose construction and connections will be set forth hereinafter.

The starting bar of the machine appears at 5, said bar being supportedby links 6 and 7, the former being pivoted at 8 to a three-armed piece 9which is pivoted to the frame of the machine at 10. A ring shaped piece11 which is pivoted to the frame of the machine at 12 is pivoted at 13to the link 7 and, also to the piece 9.

By depressing the starting bar 5 the ring shaped piece 11 is turned in acounter-clockwise direction and the pin 15 of the three- 65 armed piece9 is moved in a clockwise direction.

A lever 16 which has a slot receiving the pin 15 and which is pivoted at17, constitutes the means by which the clutch hereinafter described iscontrolled. When the starting bar 5 is in its raised position, the lever16 is so disposed that the clutch is thrown out but when the startingbar 5 is depressed, the clutch is enga ed.

The clutch mechanism an parts allied thereto are contained within acasing 18 which is securely, though detachably, fastened to the base 1by screws 19. This casing has a flanged surface or face at its rightside, Fig. 1, which serves as an end shield for the motor 20 when thelatter is attached to the casing by the screws 21.

The gear casing 18 is provided with a suitable bearing 22, Fig. 3, forthe armature shaft 23 of the electric motor 20, the other bearing forthe armature shaft being located at 24. Suitable lubricantA containersor grease cups 25 are provided for the bearings aforesaid.

Fibre washers 26 are provided on the armature shaft to take whateverendl thrust occurs between the shoulder on the armature shaft and thebearing 22.

Sleeved on the armature shaft 23, but not mechanically connectedthereto, is a worm pinion 27 which is driven from the armature shaft,with adaptability to slip slightly to prevent, or absorb, the shocktransmitted to the drive piece 3 incident to the sudden clutching actionwhich occurs when the clutch is thrown in and thus to prevent undueshock being transmitted to the mechanism of the calculating machine. Theoperating connection for the worm pinion 27 also permits slippage asbetween the worm pinion and the armature shaft 23 in the event that thecalculating machine, or certain units thereof, become accidentallystalled or locked. The connection now to be described serves as a safetydevice for the foregoing purposes.

Referring to Fig. 3, a driving pin 28 is 'securely Afastened tothevarmature shaft 23 and is received in the slots 29 of'a stop collar 30which is sleeved 0n the armature shaft 23 (Figs. 3, 6, 7). A frictionwasher 31 of any suitable material is interposed between the stop collar30 and the end of the worm 27. This construction provides a frictiondrive for the worm 27 at the right hand end thereof. At the left handend of the worm, Fig. 3, there is located another lfriction washer 31against which bears a steel washer 32. The armature shaft is rovidedwith a screw threaded end on w ich is a castellated jamb nut 33 which islocked in its adjusted position by a cotter pin 34.

`28 engaged with the notches 29 and a ords the requisite frictionalgripping action b which the worm 27 is drlven from the sha' 23 throughthe washers 31..

Under ordinary conditions the fore oing frictional drive for the worm issu cient to transmit the motion of the armature shaft 23 through theworm 27 to the clutch, hereinafter described, and to overcomeetheresistance of the calculating machine so thatthe latter will be putthrough its cycle of operations when the startingbar 5 is de pressed.The frictional drive thus provided is not of sufficient strength,however, to drive the worm 27`if the calculating machine has, for anyreason, become accidentally locked. In that event, the motor willcontinue to operate and the armature shaft 23 to revolve but the worm 27will remain stationary, that is, there will be a slip between thefriction washers 31 and the worm. Similarly, when the starting bar 5 isdepressed, there will be such momentary slippage in the friction driveby the washers 31 as will absorb the sudden shock due to throwing in ofthe clutch and thus no appreciable shock will be transmitted to thecalculating machine which will be started in its cycle of operationsquickly, though easily.

The invention is not limited to the specic safety device previouslydescribed as it may be found desirable to safeguard the motor anddifferent mechanisms of the calculating vmachine by the employment ofother safety devices.

A grease pan or container 36 is fastened to the bottom of the casing 18by a screw 37 and is located directly under the worm 27 so that the worm27 is supplied with; lubricant. A cap 38, which is secured by screws 39to the casing 18, covers the opening through which access is had .to thenut 33, when adjustments are needed.

A stud or stub shaft 40 (Fig. 2) which is secured to the casing 18 byscrew 41, constitutes the support for the revoluble Worm Wheel 42 whichmeshes with worm 27, and for the revoluble driving plate 43, said Wheeland driving plate constituting members of the clutch.

The stud 40 has parts 44 and 45 of different diameters, part beingsmaller than part 44. The worm Wheel 42 is .mounted on suitableanti-friction bearings 46. Similar anti-friction bearings afford amounting for the driving plate 43.

The worm gear or wheel is provided with a series of engaging devices orholes 44 which are located the same distance from the center of the stud40 and are spaced apart at regular intervals.

The driving plate 43 is provided with a single hole 45 in which isadapted to slide the driving plunger or pin 46. The hole 45 is solocated that the pin 46 may register With any one of the holes 44, thepurpose being to provide for entry of the pin in the nearest hole whensaid pin is released and the revolution of the gear 42 brings one ofsaid holes opposite said pin.

The worm gear 42, driving plate 43 and pin or plunger 46 constitute areleasable clutch by lwhich motion may be communicated from pinion 27 tothe driving piece 3 of the calculating machine when the starting bar 5is depressed to permit the pin 46 to enter one of the holes 44 in thecontinuously rotating wheel 42 in a manner which will appearhereinafter.

The -driving pin 46 has a peripheral groove in its outer end which isembraced by the hooked part 47 of a restoring latch 48 (Fig. 4), whoselower 4end has a hole 49, through which passes a headed stud 50 having ascrew threaded end screwed into a hole in the driving plate 43 (F iff.2), the connection being a loose one to aord play so that the restoringlatch 48 may move toward and away from the face of the driving plate.

The upper end of the restoring latch 48 is provided with an inclined lip51.

A flat or leaf spring 52 (Fig. 10) has one end secured to the drivingplate 43 by screws 53, (Fig. 1), the remainder of the spring being freefor movement toward and away from the face of said driving plate; theextremity of the spring bears von the driving pin 46 with a constantpressure. The spring 52 tends to force the driving pin 46 toward theworm wheel 42 for the purpose of snapping said pin into one of the holes44. Normally this action of spring 52 is resisted so that the pin isheld in retracted position, as shown in Fig'. 2.

The operating lever 16 which is shown in detail in Figs. 8 and 9 isconnected by rivets 54 passing through holes therein, to a pieceu .55which, in turn, is pivoted to the casing 18 at 17.

`The forward end of the operating lever, as shown in Figs. 2, 8, 9, isbent at an angle of about thirty degrees as shown at 57 to correspondto, and co-operate with, the substantially similarly angled part 51 0nthe upper end of the restoring latch 48 (Figs. 2, 4, 5). The objectofaproviding these angled parts is toprovide for a cammlng action tooccur by which the restoring latch is released when the starting bar 5is depressed, to thus permit the spring 52 to project the driving pin 46into one of the holes 44 and, also, to automatically retract the drivingpin 46 when the driving plate 43 has made one complete revolution,assuming that the starting bar 5 has been released. If, however, thestarting bar 5 is' held in this depressed position, there will be nointerference with the part 51 o the restoring latch 48 and,consequently, the driving pin 46 will remain'in the hole 44, thusmaintaining the clutched relationship of the driving plate 43 and theworm gear 42. So long as the starting bar 5 is held depressed, the drivemechanism will repeatedly operate the driving piece 3 of the calculatingmachine.

A stop or abutment pin 58, Fig. 1, which projects from the driving plate43 receives whatever strain is applied to the restoring latch 48 andrelieves whatever strain would be transferred to the driving pin 46 whenthe angled part 51 on the restoring latch 48 engages the angled part 57on the operating lever 16.

The means employed for transmitting motion from the driving plate 43 tothe piece 3 of the calculating machine comprises links 4, Figs. 1 and 2,which are adjustably connected together by a bolt 59 and nut 60, theshank. of the bolt passing through an elongated slot in the ends of saidlinks. The links are provided with engaging corrugations or teeth toavoid any possibility of relative slippage. rlhe links carry hubs 61which are provided with hardened rollers 62. The lowerinost link isconnected to the extended end of driving stud 50 and is held by a screw63. The uppermost linkis connected to a stud 64 held by nut 65 to thedriving piece 3. Thus, wide, anti-friction connections are providedbetween the links 4 the parts 43 and 3.

Pivoted to the casing by a screw 66 is back stop pawl 67, Figs. 1, 11,12, 13, which is provided with an upwardly extending cam-shapedprojection 68 which is adapted to engage a cam roller 69 carried by thestud 50, Fig. 2. At its left hand end, the pawl 67 extends at rightangles to its length, as shown in Figs. 1l and 12, and is there seatedon a compression spring 70, Fig. 1, said spring b eing located in abarrel 71 and capable of adjustment, to regulate its tension, by anadjusting screw 72 which has a lock nut 73. By this means the back stoppawl 67 is made to resist forward movement 'when struck by a roller 69on the turning of the driving plate 43 in a counterclockwise direction.rThe slot or notch appearing in Fig. 13 receives a guiding device, 74,to prevent lateral springing ot the back stop pawl 67.

The purpose oi" the back stop pawl 67 is to eliminate swinging oroscillating movement oi' the driving plate 43. Assuming that thestarting bar has been depressed and the driving pin 46 has entered oneof the holes 44, the counter-clockwise rotation of the driving platecauses the roller 69 to strike the cam projection 68 on the back stoppawl 67 which thus aifords a buffer action due to the employment ofspring so that when the part 51 ot the restoring latch 48 engages thepart 57 of the operating lever 16 to retract the pin 46 from hole 44,the rotation of the driving plate is arrested by the back stop pawl 67.As soon as the roller 69 passes the peak of the cam 68, the latter movesupwardly and exerts a wedging action on said roller (as viewed in Figs.1 and 12) as the right hand edge of the projection 68 is slightlytapered or inclined.

A removable cover 75 is attached to the face of the casing 18 by screws76, Fig. 2, entering corresponding screw threaded holes seen in Fig. 1.The cover 75 carries an electric switch 77. Wires torni the motor 20 tothe switch enter the cover 75 through holes 78, such wires being omittedfrom the drawings for the sake of clearness.

By locating the switch on the cover 75, it is conveniently arranged foroperation and, when the cover is removed, immediate access may be had tothe operating mechanism.

When the switch 77 is turned to the on position the motor 20 isenergized and the armature shatt- 23 driven and the worm 27 is revolveddue to the rictional manner in which the worm is coupled to the shaft.The worm gear 42 is revolved by worm 27.

The angular part or cam 51 of the restoring latch 48 being engaged bythe angular part 57 of the restoring latch operating lever 16, thedriving pin 46 remains disengaged Jfrom the worm gear 42 as shown inFig. 2.

When the starting bar 5 is depressed., through the intermediatemechanism, the lever 16vis swung on its pivot 17 which results in thecam end 57 lifting clear of the cam end 51 of the restoring latch 48.Immediately this occurs, the driving pin 46 is snapped by spring 52 intothe next hole 44 which comes opposite said pin during thecounter-clockwise revolution ot the worm wheel 42. A number of holes 44are provided so 'that there will be a quick engagement of the pin 46immediately after said pin is released.

@nce the pin 46 enters one of the holes 44, the driving plate 43 isturned as a unit with the worm wheel 42 and, through the links 4, thedriving piece 3 of the calculating inachine is operated, thus puttingthe calculating machine through its cycle of operations.

Should the starting bar 5 be quickly released, as is usual in mostoperations oi a calculating machine, the lever 16 will rcsume its normalposition before the driving plate 43 has made a complete revolution andthus the cam part 57 will be positioned lll) so that it will be struc-kby the cam part 51 on the restoring latch 48 when the revolution hasbeen completed.

Prior to the engagement of the cam parts 57 and 51, however, the roller69 which is mounted on the stud 50, engages the beveled ro'ection 68 ofthe back stop pawl 67. The

ac: stdp pawl, due to the action of spring 70, serves as a bumper orbuffer to check the rotation of the driving plate and just before thecam parts 57, 51' engage, the roller 69 passes off of lthe peak of thepart 68, Whereupon the back stop pawl rises and its edge Wedges againstthe said roller. Consequently, when t-he parts 5 7, 5l engage for thepurpose of retracting the driving pin 46 from the vhole 44, the arrestof the driving plate 43 is instantaneous and there is no lash orswinging mot-ion of the driving plate. he engagement of the cam surfaces57, 5]. .results in instant disengagement of the pin 4G/'from the hole44.

The provision of the friction drive for the Worm 27 serves as a safetydevice when the pin 46 is projected into a hole 44, or Withdrawntherefrom, thus relieving the mechanism from strain at these times.

The friction drive for the Worm 27 also serves the important purpose ofacting as a safety device should the mechanism of the calculatingmachine stall or become blocked for any cause as the armature shaftwould then revolve inside the Worm and no undue strain be put upon anyof the parts of the mechanism, affording the operator ample opportunityto turn the switch 7 7 to shut ofiI the current and stop the motor.

I claim:

l. In an electric drive for calculating machines, the combination with adriving Wheel provided with engageable means, of a rotarily mountedmember, a clutching device carried by said member and adapted forengaging said engageable means of the driving Wheel, a movably mountedrestoring device carried by the rotarily mounted member adapted forretracting the clutching device to isengage it fromvthe driving Wheel,an abutment on the rotarily mounted member which takes up strain towhich the restoring device is subject, an operating device adapted formanipulation which controls the opf eration of the restoring device, andmeans cooperating with the rotarily mounted member to check it andprevent it from h aving lash or overthrow after it has turned apredetermined distance.

2. In an electric drive for calculating .ma-

chines,the combination with a drivin wheel having a' hole, of a rotarilymounte member, a spring-preed slidable driving pin carried by saidrotarily mounted member and adapted, when free, to enter said hole, amovably mounted restoring device carried by the rotarily mounted memberwhich is adapted to retract and retain, the pin free from the hole, anabutment on the rotarily mounted member Which takes up strain to whichthe restoring device is subject and releasable controlling means adaptedto cooperate With the restoring device to hold the pin in retractedposition.

3. In an electric drive for calculating machines, the combination With adriving Wheel provided With engageable means, of a rotarily mountedmember, a clutching device carried by said member and adapted forengaging Said engageable means of the driving wheel, a restoring devicecarried by the rotarily mounted member adapted for retracting theclutching device to disengage it from the driving Wheel, a controllingdevice, adapted for manipulation, which embodies a cam adapted tocooperate with the restoring device for the purpose of disengaging theclutching device from the driving Wheel, and an arresting device adaptedto cooperate with the rotarily mounted member for the purpose ofchecking its rotation just prior to the engagement of the restoringdevice with the cam means aforesaid.

4. In an electric drive for calculating machines, the combination With aframe, of rotarily mounted driving and driven elements, means forclutching and de-cl'utching said elements, means 'independent of thedriven element for controlling the clutching and de-clutching means, anda separate arresting device movably mounted on the aforesaid frameadapted to cooperate with the driven element for the purpose ofautomatically checking its rotation and preventing back-kick or swingingmovement thereof after the driven element has completed itspredetermined cycle of rotation.

5. In an electric drive for calculating machines, the combination with aframe, of rotarily mounted driving and driven elements,normally-restrained and automatically-acting means ada ted for clutchingsaid elements when re eased, controlling means for said clutching meansWhich normally restrains the said means and is also adapted toautomatically throw-out said clutching means after the driven elementhas completed its predetermined cycle of rotation, and a separatearresting device movably mounted on the aforesaid frame Which is adaptedto cooperate with the driven element for the purpose of automaticallychecking its rotation and preventing backkick or swinging movement aftersaid driven element has completed its aforesaid cycle.

6. In an electric drive for calculating machines, the combination with adriving Wheel having engageable means, of a rotarily mounted platenormally free of the driving Wheel, a movably mounted clutching devicecarried by the rotarily mounted plate which is adapted, when free, toengagethe engageable means of the driving Wheel, a movable restoringlatch carried by the rotarily mounted plate and cooperating with theclutching device aforesaid, spring means for actuating the clutchingdevice When the latter is free to cause said clutching device to engagethe engageable means of the driving wheel, a controlling device having acam engageable with the restoring latch when the rotarily mounted plateis 1n a predetermined position to release the clutching device from thedriving Wheel and against the action of the spring means aforesaid, anda movable. spring actuated, back stop pawl adapted to check or arrestthe rotation of the plate aforesaid just prior to the engagement of therestoring latch with the cam of the controlling device.

7. ln an electric drive for calculating machines, the combination with adriving wheel having engageable means, of a rotarily mounted plate. adriving pin slidably car ried by the plate and adapted, when free, toengage the engageable means of the driving wheel,I a movably mountedrestoring latch carried by, and rotatable with, the plate and engagedWith said pin. said latch having a cam. an abutment on the rotarilymounted plate Which takes up strain to which the restoring latch issubject, a spring carried by the plate which engages the pin and isadapted to cause said pin to engage the engageable means of the Wheelwhen said pin is free, and an operating lever provided with a cam whichis normally positioned for engagement by the cam of the restoring latchbut which may be manipulated to disengage its cam from the cam of thelatch to permit the pin to clutch the driving Wheel.

8. In an electric drive for calculating machines, the combination with adriving wheel and a rotarily mounted member having means by Which it maybe clutched to, or de-clutched from, the driving Wheel, of meanscontrolling the clutching and declutching action aforesaid, a sprinactuated back stop paWl having a cam sur ace and a shoulder, and adevice on the rotarily mounted member adapted to ride on the cam of saidpawl and then to be engaged by said shoulder when the parts are assumingcle-clutching position, said pawl thus serving to check the rotation ofthe rotarily mounted member and to prevent it from swinging whende-clutching has been eected.

In testimony whereof I affix my signature.

FREDERICK W. BERNAU.

